September swoons are nothing new in presidential politics. Look back at almost any competitive election and you’ll find one of the candidates hitting turbulence — and pointed second-guessing — at this time of the year.

That’s the good news for Mitt Romney as he struggles with poll numbers that show him trailing President Obama in some key states, growing unease among Republicans about their nominee and his team, and reports of disarray in his campaign. He’s not the first to face this situation.

The real test is how he responds. The history of campaigning suggests that, at such moments, much more depends on the candidate’s performance than that of his team. It is a leadership test in real time. What he says and does on the trail in the coming days and, far more important, how he conducts himself in the first presidential debate should answer that question.

The latest heartburn for the Romney team came Monday with the release of a leaked video of the candidate at a fundraiser claiming that he’ll never win the support of 47 percent of the electorate because they are dependent on government and can’t be persuaded that “they should take personal responsibility for their lives.”

That came after another setback on Sunday night, when Politico reported on the chaotic process of writing the candidate’s acceptance speech for the Republican convention and aired criticism—none of it on the record—of chief strategist Stuart Stevens. To most voters, this is inside baseball. But it was the kind of story that often appears when things are at their worst and most stressful inside a campaign.

Veterans of past campaigns know what the Romney team is feeling. Mark McKinnon, who was George W. Bush’s chief media strategist, said the Bush campaign went through the same thing in 2000. “We called it Black September,” he said. “Everything went to [pieces]. Everybody was saying we should be fired. It’s eerily similar.”

Four years ago, Obama’s campaign was under fire in the weeks after the two political conventions ended. Sen. John McCain (Ariz.), the GOP nominee, whose campaign received a boost by the selection of then-Alaska Gov. Sarah Palin as his running mate, overtook Obama in the polls.

Democrats were pounding on the Obama team, so much so that campaign manager David Plouffe dismissed as “hand-wringing and bed-wetting” the complaints coming from fellow Democrats. Obama was concerned enough about what was happening that he called a meeting of his senior advisers on a Sunday night and told them to step up their game.

The next day, Lehman Brothers went bankrupt, triggering the economic collapse and sealing McCain’s fate. Before the end of the campaign, McCain’s operation was a house divided, bitterly airing its differences in public even before the polls had closed on Election Day.

This year, it’s unlikely that Romney can count on some unexpected event like the economic collapse of 2008 to deliver the White House. But should he need that kind of help? He already has what many Republicans regard as a golden opportunity to defeat an incumbent. With the economy still in trouble and the Middle East awash in protests, Republicans wonder why Romney isn’t in a more secure position with seven weeks left in the campaign.

Tad Devine remembers similar periods of outside criticism and internal duress in two Democratic campaigns in which he played senior roles: Al Gore’s 2000 election bid and John F. Kerry’s 2004 race. He sees only one path for Romney. “He’s the only guy who can save his campaign right now,” Devine said. “He can have different people in different decision-making capacities. But he’s the only guy who can make this work.”

This isn’t the first time Romney’s campaign has come under criticism. There were quiet calls for staff changes during the primaries and later complaints about the team’s operations from notable business leaders such as News Corp. Chairman Rupert Murdoch and Jack Welch, a former chief executive of General Electric.

Romney, an experienced businessman and manager, has put together a campaign of disparate personalities. Campaign manager Matt Rhoades is as buttoned-down as Stevens is mercurial, free-spirited and a lightning rod for criticism. Romney seems to have bonded with both, along with loyalists from his days at Bain Capital, his time as Massachusetts governor and his 2008 presidential campaign.

It’s doubtful that Romney would consider pushing out some of his people now. Tweaking perhaps, but little more. The core team of advisers, which has remained virtually the same from the start, helped him win a tough fight for the nomination of a party whose base resisted him from the beginning. Infighting in campaigns is the norm, not the exception. Romney’s team has no choice but to battle through the strategic disputes and personality clashes.

There is another reason staff changes aren’t likely. The turmoil wouldn’t be worth it. Romney would lose a week or more to the story at a time when every day is critical. Some Republicans who are loyal to Romney have concluded that Obama’s team has run a better campaign, but they still say that, given economic conditions, the president is vulnerable and Romney can win.

Obama outspent his rival on television ads during the conventions, a decision by the GOP nominee’s team that outsiders are second-guessing. Romney has the money to spend freely now. But as one strategist noted, drawing back voters who may have slipped away during the summer will be harder now.

Romney advisers note that the Gallup tracking poll that showed the president with a six-point lead last week now shows the rivals separated by three points. That’s better than things looked a week ago, but Obama’s three-point margin is still significant, given how stable the race was for so many months. And the president’s approval rating in the Gallup track has held at 50 percent since the Democratic convention.

That’s why so much depends on Romney. In the estimation of allies and opponents, Romney still hasn’t found his voice as a candidate or a message compelling enough to win over persuadable voters. To these strategists, he hasn’t risen to the challenge of defining his presidency. In Devine’s words, Romney needs real substance, not “fluffy substance,” in his message.

Romney has an opportunity to define real substance as he tours the country over the next two weeks. But the most opportune moment will come on Oct. 3, when he and Obama will meet in Denver for the first of their three presidential debates. That first face-to-face contest, McKinnon said, is “the best and maybe last chance” for Romney to turn the campaign decisively in his direction.

One GOP strategist close to the campaign, who spoke on the condition of anonymity to offer candid advice, said that this is a time in the election cycle when voters begin to take a last good look at the candidates and that the first debate must be the moment for Romney to rise.

If he doesn’t do well there, the strategist concluded, “I am not sure folks will pay as much attention to later ones.”

Past candidates have used debates to change the race, even if temporarily. Amid doubts and criticism, can Romney do the same?